Attack of the dromedaries


It's sunrise on the Colorado River, and a dozen sand-colored lumps stir by the banks. Bodies rise on spindly legs. Mouths open with a sound like pulling dentures. In a flash of gums, twelve sets of teeth clamp down on the nearest tamarisk plants. Chomp. Chomp. Leaves, bark and thorns disappear in a rhythm of steady chewing. The year is 2011, and the camel invasion has begun.

Such a future would make rancher Maggie Repp proud. While camels are known for three things -- they spit, they have humps, and they can survive for long periods without water -- Repp, the owner of 15 camels in Loma, Colo., believes they could be great at controlling tamarisk. The tough, salty tamarisk bushes are perfect camel food. "They will eat all day if given the opportunity," says Repp, who  plans to set up a demonstration project this spring. "My camels have killed every tamarisk on our place, so why not give it a whirl?" 

Photo credit: Ltshears

The invasive tamarisk is notoriously hard to kill. First introduced from Eurasia to the U.S. in the 1800s, it spread relentlessly across the West, choking up rivers and out-competing native plants (for a history of the tamarisk, see Paul Larmer's 1998 article "Tackling Tamarisk"). Tamarisk has survived chainsaws, fire and chemical herbicides. In 2001, scientists released the foreign Diorabda beetle to control the plant's spread. Since then, the leaf-eating beetles have attacked thousands of acres of tamarisk (see Michelle Nijhuis' 2007 story Beetle Warfare).

But even a brown, leafless tamarisk can spring back to life. It sometimes takes several years of de-leafing by beetles to kill a tamarisk, and camels would work in much the same way. Repp hopes the camels will eat away at any new growth until the tamarisk finally dies. In an effort to publicize her plan, she left some pamphlets at the 2010 Tamarisk Symposium, where hundreds of people had gathered to discuss tamarisk beetles and their effects on the endangered Southwestern willow flycatcher.

"I've heard of people using goats," said one scientist. "But it would take a LOT of goats [to really get anywhere]." Camels, he said, would likely pose the same problem.

Repp estimates that 10 camels could destroy half an acre of tamarisk in 2 days. That's small-scale compared to tamarisk beetles, which can spread over a hundred miles in two years. So for full riparian restoration, stick with the beetle. But if you want to clear the odd tamarisk patch off your pasture, it might be easier to rent a camel.

Anonymous says:
Jan 20, 2010 03:47 PM
Great job on the camel article! Did you tour the ranch? I really want to make a trip out to the All's Welcome ranch myself. It was good meeting you at the Tamarisk Symposium.
Grace L
Anonymous says:
Jan 20, 2010 05:47 PM
As the Australians about turning camels loose on an arid land. Camels were used for early transportation in the dry Australian outback. The were perfect. Unfortunately when they were liberated after no longer being used for transportation, they took over. There are now millions of them munching the outback in a decidedly no specific manner. When the salt cedar is gone, they will eat everything, and reproduce prodigiously. My wife and I spent a year riding our tandem bicycle around the outback of Australia; we saw sign everywhere, and heard them clomping around our tent at night. Whatever you do, do not let them roam free.
Anonymous says:
Jan 21, 2010 10:52 AM
Anonymous says:
Jan 21, 2010 05:14 PM
The Conservation District of Laramie County Wyoming uses leased/rented goats to "storm" graze riparian corridors through Cheyenne, Wyoming with great success. The goats are confined by electric fence to long narrow stretches of Crow and Dry Creeks and clean them up in less than a week. I can imagine camels being used similarly; although southwestern riparian areas would have a lot of access problems.
Anonymous says:
Jan 29, 2010 11:32 AM
I could not agree with Bob Rogers more. Camel are an alien spieces to North America and introducing them would be wrong. In a recent article I read that the Australians are considering culling the vast herds of camel in the outback to prevent more damage. Earlier there was a massive problems with rabbits which had been introduce into Australia and which caused untold damage to native flora and fauna.
Introducing alien spieces causes harm. In the late 19th Century North American grey squirrels were introduced into the British Isles. The originals were actually a wedding present and they escaped into the wild. Now the greys have all but wiped out the native red squirrel. The grey carry a pox that is fatal to the red, they are also larger, more aggressive and don't hibernate like the reds.
Other spieces introduced or escaped into the wild in the British Isles have also caused huge damage. Mink and North american crayfish are two notable examples. Plants and birds also contribute to the unbalancing of the native eco-system as alien plants and wildlife seem to be more invasive than the native varieties.
No matter how well intentioned or how well controlled the introduction of alien spieces always seems to end in grief and should not be considered.
Anonymous says:
Feb 16, 2010 01:51 PM
It is Rogers and Green who are wrong! The Camelidae evolved in North America and there were several species of them there when Central Asians arrived at the close of the Pleistocene. Those people were eventually called Native Americans, and they wiped out nearly all the NA megafauna. Rogers and Green have not done their homework.

I expect the primary objectors will be ranchers that want all the vegetation for their cattle. Indeed, it is ranchers that howl at wolf reintroductions. Because of that and several other reasons I have quit eating beef. I would rather have megafauna to enjoy watching, and even eating, than that most unhealthy of meats, beef. Imagine how much land would become available for ecosystem restoration if everyone quit beef. Join us!

The Pleistocene Park concept may be an unrealistic idea to get the gubmint to accomplish - selfish, conservative ranchers have just too much political power for our own good. Progressive ranchers like Maggie Repp, OTOH, could get it done. Good for her! And thank you, Lisa Song, for your upbeat and inspiring article. And thank you, Rogers and Green, for your home run pitches!
Anonymous says:
Feb 23, 2010 10:16 PM
I love camels and collect everything camel, so my friend, Adele, made sure I got this article. I've never been to Colorado, but knowing that there are camels there makes a trip very tempting. They don't deserve the bad rep they've earned. All the camels I've met so far have been very sweet and dopey. Hooray, for camels!
Anonymous says:
Mar 08, 2010 02:39 PM
I'm glad that camels are working on tamarisk. But maybe we could make things easier on ourselves and just use a tool we've already got - cows. I've been teaching cows to eat weeds since 2004. Based on what I've learned I know that I could teach them to eat Tamarisk too. We have a lot of cows in areas where we have a lot of tamarisk so using them is cheaper than buying camels or renting goats. All we have to do is manage them differently.

To learn more about weed-eating cows you can visit my website at:
Anonymous says:
Apr 27, 2010 09:37 AM
Not for the faint of stomach.